Range

The range of a player contains all played hands that are available in the current situation.

When playing poker the first step on becoming more advanced is to think in hand ranges than just in single hand combinations. What range could a player have in a certain spot is a very important piece of information to make good decisions.

While a range is always a part of all possible hand combinations, there are special sub terms to define certain style of ranges:

Openraising-Range
The range a player is openraising preflop with from each spot at the table

Pushing-Range
The range of hands a player pushes all-in, for example in poker tournaments when the stacks get shallow in comparison to the blind

You also need ranges to calculate the equity for your own holding. The EV of your holding is the sum of win possibilites against each hand out of the range of hands your opponent has over all possible outcomes. So in order to assess your own equity you need to be able to define the range of hands your opponent is likely to play in a spot. This hand, or better range-reading ability is key to becoming a better player and making better decisions at the table.